661 has an ankle brace that will assist. I am generally against them as they don't allow your muscles to develop.

Personally I would take on a plyometric routine similar to what basketball players do. Standing jumping two foot, single foot
Box jumps up
Box jumps down
Standard Calf raises however using MASSIVE weight. Calves get worked constantly when you walk, jump, pee etc..., do the opposite when you workout, attack them with loads of weight they aren't used to. Get enough weight on your shoulders so you can only do 8 to 15 TOPS. Massive weight also strains the muscles differently, as well as the tendons and bones. All of which will help get rid of sprains.

In the process you will also develop explosive muscle power (not necessarily strength) which will assist in all aspects of riding.

Also, and this is a the bad note, weak ankles is rarely a muscle thing, I have massive leg strength and size, especially in the calves, and have always had small ankles. I fight with sprains almost constantly. Things have gotten better as I strengthened them, but its a long slow process and you will always suffer from it.

also get a pair of 3/4 top sneakers with ankle support, like the 661 dually.
I have bad ankles, I sprained them a bunch of times playing football, so they are kinda shot. I wear the duallies(the 2004 model, they have the best ankle support) and i also wear and ACE slip on brace for extra support. and i've had little problem while dropping.

661 has an ankle brace that will assist. I am generally against them as they don't allow your muscles to develop.

i've got these; they do only a little bit to brace. i use them when at the lifts, more as extra ankle protection against rocks and so on. i don't count on them to prevent an ankle rolling, but any little extra help they give, i'll take.

K so I ride hardtail freeride and the drops have been severly spraining my ankles. What type of exersize can i do to burly them up??

This is a very tricky exercise. What I suggest is doing ankle rotations with resistance. Basically, instead of spinning your ankle around, you resist it with your arm. Of course as you go around in a circle you will have to change how you apply the resistance.

It takes some getting used too, but this exercise will both strengthen and stretch.

This is a very tricky exercise. What I suggest is doing ankle rotations with resistance. Basically, instead of spinning your ankle around, you resist it with your arm. Of course as you go around in a circle you will have to change how you apply the resistance.

It takes some getting used too, but this exercise will both strengthen and stretch.

What I would consider the first proper response. Calf strenth has little to do with ankle flexibility. You must stretch the tendons and ligaments. We used to walk on the outsides of our feet before football practice, then do exercises similar to what willtsmith described and we had a ultra low rate of sprains (3 people in 4 years). It takes time, but you have to build up flexibility. Braces will do the opposite and I stay as far away from them as possible.

For ankle support, I recommend ankle braces, I destroyed my left ankle in an accident, now my left ankle dislocates very easily, I wear ankle braces similar to the 661 ones but mine is no name, better and cheaper (got it from sportsmed, an AAustralian sports injury specialist place). I also have a wobble board from my rehab (circular disc with a hemishpere on the bottom, you balance on it. This wobble board increases calf muscle and strengthens your ankles.